Long travel dual sill cushioning arrangement for railroad cars



Aug. 8, 1967 w. H. PETERSON LONG TRAVEL DUAL SILL CUSHIONING ARRANGEMENT FOR RAILROAD CARS 4 Sheets-Sheet 1 Original Filed March 15, 1965 INVENTOR WILLIAM H. PE TER N ATT'YS.

Aug. 8, 1967 w. H. PETERSON 3,334,757

LONG TRAVEL DUAL sILL CUSHIONING ARRANGEMENT FOR RAILROAD cARs Original Filed March 15, 1965 4 Sheets-Sheet 2 INVENTOR WILLIAM H PETE 0N ATT'YS.

Aug. 8, 1967 w. H. PETERSON 3,334,757

LONG TRAVEL DUAL SILL CUSHIONING ARRANGEMENT FOR RAILROAD CARS Original Filed March 15, 1965 4 Sheets-Sheet 5 Aug. 8, 196 w. H. PETERSON LONG TRAVEL DUAL SILL CUSHIONING ARRANGEMENT FOR RAILROAD CARS 4 Sheets-Sheet 4 Original Filed March 15, 1965 INVENTOR United States Patent 3,334,757 LONG TRAVEL DUAL SH..L CUSHIONING ARRANGEMENT FOR RAILROAD CARS William H. Peterson, Homewood, 11]., assignor to Pullman Incorporated, Chicago, 11]., a corporation of Delaware Continuation of application Ser. No. 439,631, Mar. 15,

1965. This application May 16, 1966, Ser. No. 562,990 5 Claims. (Cl. 213-8) ABSTRACT OF THE DISCLOSURE A railway vehicle including a Wheeled frame structure having a draft and buffing column carried thereby with couplers attached to the respective ends of the draft and butfing column. A cushioning means is operatively interposed between stop means fixed on the frame and the column for cushioning longitudinal impacts applied to the couplers. The column comprises a pair of sections positioned in spaced apart relationship and in longitudinal alignment for movement longitudinally with respect to each other and to the frame structure. A keying means is formed in the adjacent ends of each of the columns and a cushion pocket is formed outboard of each of the keying means. A resilient cushioning device is mounted in each of the cushion pockets for engagement with the stop means so as to be operative to absorb draft impacts applied on the column when the column sections are in the spaced position. A hydraulic cushion is disposed between the sections and includes a hydraulic fluid filled cylinder and a piston assembly reciprocal therein. The cylinder and piston assembly have a length of travel substantially equal to the spaced distance between the column sections. The cylinder and the piston assembly have means on the respective ends for keying to the column sections. A return spring is disposed between the cylinder and the piston assembly.

This is a continuation of US. patent application Ser. No. 439,631 filed Mar. 15, 1965, now abandoned.

My invention relates to a long travel dual sill cushioning arrangement for railroad cars, and more particularly, to a railroad car cushioning arrangement of the sliding sill or draft and bufling column type that is especially adapted to provide long travel cushioning benefits for all impact situations with which the car will in practice be involved.

Railroad car cushioning arrangements most commonly employed at the present time for box cars and the like are the so-called sliding sill or draft and bufling column arrangement, and the so-called end of car cushioning arrangements. While the principles of long travel cushioning may be applied to both of these cushioning arrangement types, end of car cushioning having travels in cushion travel ranges much in excess of conventional draft gear travel has not been widely adopted because of the train slack problem, and sliding sill type arrangements have the limitation that when the cushion car is disposed in a string or line of cars and is impacted during train operation the sliding sill arrangements and cushion units used heretofore do not provide cushioning after the initial impact has been dissipated and the cushioning unit returns to its normal non-impacted position so that excessively rapid run-in and run-out of slack may occur.

A principal object of my invention is to provide a new and improved cushioning arrangement of the sliding sill or draft and butting column type which provides for long travel cushioning protection which obviates the difiiculties encountered heretofore during train action.

Another principal object of my invention is to provide a conversion cushioning assembly for readily converting standard box cars and the like (cars having conventional draft gear cushioning only) to cushion underframe cars.

Yet another principal object of my invention is to provide a novel center of car long travel cushioning device of the hydraulic type that is arranged to protect itself against overload conditions that can be created by excessive speed-high mass impacts.

Still another principal object of the invention is to provide a cushioning arrangement for sliding sills of the dual sill type in which each section of the sill is connected by a double acting hydraulic cushion having a substantially constant force travel characteristic upon butt impact and during the return stroke after a buff impact has been dissipated.

It is still a further object taken in conjunction with the immediately foregoing object to provide a resilient cushioning means which is operative to cushion draft impacts under conditions in which the sill sections and hydraulic cushion are in neutral positions.

Additional objects of my invention are to provide a simplified and more compact hydraulic cushioning arrangement, to provide a simplified assembly arrangement and method for converting standard box cars and the like to cushion cars, and to provide a cushioning arrangement for railroad cars that is inexpensive of manufacture, convenient to install in new or old cars, and efficient and long lived in operation;

Other objects, uses, and advantages will be obvious or become apparent from a consideration of the following detailed description and the application drawings.

In the drawings:

FIG. 1 is a plan view diagrammatically illustrating a railroad car underframe having the sliding sill or draft and bufiing column cushioning arrangement of this invention applied thereto;

FIG. 2 is a diagrammatic side e-levational view of the fixed center sill of the underframe shown in FIG. 1 and the sliding sill type cushioning arrangement that is associated therewith in accordance with this invention, with the cushioning arrangement displaced below the underframe fixed center sill to better illustrate the components involved;

FIG. 3 is a fragmental diagrammatic exploded perspective view illustrating the principal components of the cushioning arrangement embodiment illustrated in FIGS. 1 and 2, together with the adjacent portion of the underframe fixed center sill and the lugs and stops that couple the sliding sill arrangement with the fixed center sill to provide for transmission of impact forces therebetween;

FIG. 4 is a fragmental cross-sectional view substantially along line 4-4 of FIG. 1;

FIG. 5 is a fragmental cross-sectional view substantially along line 55 of FIG. 1;

FIG. 6 is a longitudinal cross-sectional view through the hydraulic cushioning unit that forms a part of the cushioning device of FIGS. 1-5 taken substantially along line 66 of FIG. 1;

FIG. 7 is a fragmental large scale sectional view illustrating a portion of the piston pressure relief valve that is shown in FIG. 6; and

FIG. 8 is a diagrammatic perspective view in section of the hydraulic cushioning unit shown in FIGS. 6 and 7, parts being omitted to better illustrate other parts.

However, it is to be understood that the specific drawing illustrations provided are supplied primarily to comply with the requirements of 35 U.S.C. 112, and that the invention may have other embodiments that will be obvious to those skilled in the art.

General description Reference numeral of FIG. 1 generally indicates a sliding sill or draft and bufling column cushion underframe arranged in accordance with this invention in which the car body underframe 12 has applied thereto a sliding sill or draft and buffing column cushioning arrangement 14 that is arranged to provide long travel cushioning characteristics of the type described in my Patent 3,003,436.

The underframe 12 is shown only diagrammatically as it may be any conventional type of underframe and thus may include side sills 16, end sills 18, bolsters 20, cross bearers 22, cross ties 24, and fixed center sill 26, all of which may be arranged and secured together in any conventional manner. In FIG. 1, these familiar underframe components are illustrated in broken lines only, although the fixed center sill 26 is more fully illustrated in FIGS. 2-5.

The fixed center sill 26 is shown as the usual and customary Z-26 type and thus comprises a pair of Z members 28 and 30 fixed together as by welding at 32 to define a downwardly opening channel shaped center sill structure forming the usual chamber 33 in which the sliding sill is to be mounted.

In accordance with this invention, the sliding sill or draft and boiling column cushioning arrangement 14 which is received in chamber 33 comprises a pair of column sections 34 and 36 positioned in spaced apart arrangement in longitudinal alignment and having like ends 38 and 40 thereof operatively secured to a center of car cushioning device 42.

Further in accordance with this invention, the cushioning device 42 at the respective ends 44 and 46 thereof is provided with keys or lugs 48 and 50, respectively, that are adapted to be received in the respective key slot structures 52 and 54 that form a part of the respective sill section ends 38 and 40.

The sill sections 34 and 36 adjacent their respective ends 38 and 40 are formed to define the respective cushion pockets 56 and 58 in which are respectively mounted rubber pad type resilient cushioning assemblies 60 and 62, each of which is T-shaped in transverse cross-sectional configuration and which include a follower 63. Each column section is formed with a pair of opposed stop or abutment structures 64 and 66 on either side of the respective cushion pockets 56 and 58, with the cushion devices 60 and 62, respectively, abutting against the respective stop structures, as indicated in FIG. 1.

The center sill structure 26 is provided with a pair of stop structures 68 and 70 that are intended to engage against the respective follower plates 63 of the respective cushioning devices 60 and 62 when the cushioning arrangement 14 is operatively mounted within the underframe 14. Spaced tie members or bars 72 and 74 are fixed to the center sill structure 26 vertically below the stop structures 68 and 70 and have secured thereto similar stop structures 76 and 78 that are to engage against the respective follower plates 63 of the cushioning devices 60 and 62 in a similar manner when the cushioning arrangement 14 is in its operative position. A cushion support platform or plate 80 is fixed to the center sill structure 26 beneath cushion device 42 to hold the cushion device 42 in its operative position between column sections 34 and 36.

Cushioning device 42 includes the novel hydraulic cushioning unit indicated at 82 in FIGS. 6 and 8, the essential features of which are disclosed in my copending application Ser. No. 439,630, filed Mar. 15, 1965, now abandoned, the disclosure of which is hereby incorporated herein by this reference. Hydraulic cushioning unit 82 includes a novel piston pressure relief valve arrangement '83 for protecting the cushioning unit 82 against excessive speed-high mass impact situations.

In use, the fixed sill stop devices 68 and 70 are applied to the fixed sill 26 in any suitable manner and the column sections and cushioning device 42 are mounted within the center sill structure 26 in any appropriate manner. Cushion support platform or plate is positioned below the cushioning device 42, and the tie bars 72 and 74 are positioned underneath the column section ends 38 and 40, all substantially in the manner indicated in FIGS. 2 and 3, and by being fixed to the lower portion of the center sill structure 26. Additional supports for the column sections may be provided as may be necessary or desirable in the manner usual for sliding sills, as at the underframe bolsters, cross bearers, end sills, etc.

In operation, when buff impacts are occasioned, the hydraulic cushioning device 42 contracts for its length of travel, which preferably is in the range from about 20 to about 40 inches, thereby contracting the draft and buffing column at the center of the car, with the cushion force being applied to the car underframe through the appropriate stop devices or structure 68 or 70, depending upon which end of the car is impacted. Draft impacts are cushioned by the respective resilient pad cushioning devices 60 or 62, depending on which end of the car is draft impacted, when the hydraulic cushion device 82 is in the neutral position as to be more fully explained hereinafter.

The cushioning arrangement of this application is particularly useful in converting standard uncushioned boxcars and the like (cars with standard draft gear cushioning only) to cushion underframe cars, but also is highly suitable for use in new cars as well.

Specific description Underframe 10 may be of any type known to the art, and is only diagrammatically illustrated in FIG. 1 (in which it is shown in broken line), to show a familiar structural environment that specific embodiments of this invention will ordinarily be associated with. The center sill structure 26 is conventional in nature, except as modified in accordance with this invention, and defines outwardly directed flanges along its lower edges to which the tie members or bars 72 and 74 and the cushion support plate or platform 80 are afiixed in any appropriate manner, as by the bolts 92 and 94 shown in FIGS. 4 and 5. In accordance with the specific arrangement illustrated, the flanges 90 on either side of the position that the cushion device 42 is to occupy have afiixed thereto spaced angle members 96, as by employing bolts 93, to which plate or platform 80 is aflixed by the aforedescribed bolts 94; plate 80 includes spaced downwardly extending flanges 98 on either side thereof that are afiixed to the angle members 96 by the aforesaid bolts 94.

The column sections 34 and 36 are similar in nature and each is made up of a beam 100 that has an H-shaped configuration in transverse cross section (see FIG. 4), and as indicated in FIGS. 1 and 2, the beams 100 at the column section ends 102 have operatively connected thereto in any suitable manner conventional coupler 104. The attachment of the coupler to the respective column sections may be done in any suitable manner, but preferably the coupler is pivotally secured directly to the column section, as indicated in the drawings, and the customary draft gear is eliminated, as the cushioning devices 60 and 62 serve the purpose of draft gear in accordance with this invention. In the coupler attachment arrangement shown in the drawings, coupler housings 101 are fixed to the outer ends of the column sections, and the coupler 104 is attached for swinging movement by pin 103 carried by coupler support 105 disposed between a tie plate 107 fastening the housing 101 to the column section, and stops 109 fixed in the housing 101. Reference may be had to my copending application Ser. No. 196,320, filed May 21, 1962, for a more detailed description of the coupler housing and mounting structure.

The beams 100 thus define a beam structure having vertically disposed flanges 106 connected together by a web 108. V

The column sections 34 and 36 at their ends 38 and 40 have their webs 108 removed as at 111 to define cushion pockets 56 and 58 and receive structural units 110 which define and comprise the respective slot structures 52 and 54. Units 110, which are preferably in the form of castings, are shaped to define the illustrated T-shaped slot 112 in each unit 110. The slots 112 are proportioned to complement the shape of the respective T-shaped lugs or keys 48 and 50, and as indicated, the respective slots 112 and lugs or keys 48 and 50 have a dove tail lug and slot type relation for interlocking the cushion device ends 44 and 46 with the ends 38 and 40 of the respective column section ends. As indicated in FIG. 3, the units 110 are preferably arranged so that the slots 112 are vertically disposed when the column sections are in their operative positions with respect to the car underframe, and thus the cushioning unit 42 may be applied to the underframe sections by vertically aligning the respective cushion device lugs or keys 48 and 50 with the respective slots 112 and then elevating the cushion unit into place to dispose the respective lugs within the respective slots.

Units 110 are preferably afiixed to the respective column section ends 38 and 40 by welding or the like, and the column section ends may be cut away as at 116 to permit U-shaped welds to be applied as at 118. The castings 110 are formed with grooves 120 to receive the remaining side portions 122 of the respective webs 108, and it will thus be seen that units 110 can be readily slid onto the respective column section ends 38 and 40 for welding in the indicated positions.

The cushion pockets 56 and 58 are thus defined by the faces 124 of castings 110, the stop structures 64 and the web side portions 122. Faces 124 of castings 110 form the aforementioned stop structures 66.

The stop structures 64 of the respective column sections each comprise a pair of blocks 126 and 128 afiixed as by welding to the upper and lower surfaces 130 and 132 of the column section webs 108, with the end faces 134 of the blocks 126 and 128 being in vertical alignment with the web interruption end 136.

The cushioning devices 60 and 62 each comprise a plurality of resilient pads 140 (made from, for instance, rubber) adhered to the opposite sides of metallic separating plates or discs 142, in accordance with known arrangements for resilient pad cushioning devices. Associated with the pads and plates 140 and 142 at one end of each cushioning device 60 and 62 is a follower plate 63, and as indicated in FIG. 3, the pads 140, the plates 142 and the follower plates 63 are given the T-shaped configuration indicated inthe drawings, with these parts being proportioned to that their downwardly extending or depending portions 146 are received within the interruption 111 formed in webs 108 to form pocket 58, with the upper portions 148 of these elements being enlarged to define shoulders 150 that rest on the respective web side portions 122 about the cushioning devices 60 and 62 within the column sections 34 and 36.

As also indicated in the drawings, the resilient cushioning devices 60 and 62 are positioned so that follower plates 63 abut against stop structures 64 of each pocket and stop structures 68, 76 and 70, 78 that are adjacent the respective pockets. It is preferable to apply the cushioning devices 60 and 62 within cushion pockets 58 with a prestressing on the order of that conventionally used in such devices. 3

Stop structures 68 and 70 each comprise a block 160 afiixed to a base plate 162. The top portion 164 of center sill structure 26 is formed with a pair of openings 166 which receive the respective blocks 160 in a position to dispose their end surfaces 168 in engagement with the respective follower plates 148. Base plates 162 and blocks 168 are welded to the center sill structure 172 a suitable block 174 that forms the respective stop structures 76 and 68. Channel members 170 should be fixed between the flanges 90 of the center sill structure in a position appropriate so that faces 176 of blocks 174 will be in abutting engagement with follower plates 63 of the cushioning devices and 62, when the cushioning devices are in their assembled position.

Thus, thefaces 134,168 and 176 of the stop devices 64, and 78 for column section 36 should be in substantial vertical alignment, while the faces 134 and 168 and 176 of the stop devices 64, 68 and 76 of the column section 34 should be in substantial vertical alignment.

Hydraulic cushioning device The hydraulic cushioning device 82 (see FIGS. 68) includes a piston member 220 defining a piston head 222 and a piston rod 224 which is aflixed to the lug or key structure 48 that forms the cushion end 44.

Hydraulic cushioning device 82 further comprises a housing 232 which has afiixed thereto the lug or key structure 50 that forms the end 46 of cushion device 42, and mounted in housing 232 is a cylinder 234 in which the piston head 222 operates. Pressure relief valve device 83 is operably associated with the piston member 220..

The hydraulic cushioning device housing 232 comprises a shell or casing 270 of generally quadrilateral transverse cross-sectional configuration, which may be defined by a pair of channel shaped members 272 welded together as at 274. Associated with the casing or shell 270 are end plates 276 and 277, which also mount between them cylinder 234 in which piston member 220 operates. Integrally united with end plate 277 is the lug or key 50.

As indicated in FIG. 6, the end plates 276 and 277 are each formed with recesses indicated at 278 and 280, respectively, in which the ends 282 and 284 of the cylinder 234 are respectively received. The end plates 276 and 277 are also recessed as at 286 and 288, respectively, to receive the respective ends 290 and 292 of the shell or casing. The end plates 276 and 277 are secured to the cylinder and shell or casing respectively by welding, as indicated in FIG. 6, although any other suitable means of securement that provides an effective hydraulic seal may be employed, as will be understood by those skilled in the art.

As clearly indicated by FIGS. 6 and 8, the cylinder 234 defines with the end plates 276 and 277 a working chamber 294 in which the piston member head 222 operates. The casing or shell 270 defines with cylinder 234 and end plates 276 and 277 an annular reservoir 296 for hydraulic liquid with which the cushioning device 82 is filled, as through a port 297 in shell or casing 270 (see FIG. 6) which may be sealed off by a suitable plug 298.

The cylinder 234 is preferably formed with a plurality of orifices 300 that are arranged to provide a substantially constant force travel characteristic when the piston member 220 is moved, relative to cylinder 234, or vice versa, under buff impacts from the full line position of FIG. 6 to the broken line position of that figure. This may be done in any conventional manner, as by making orifices 300 all of the same diameter and spacing them at the varying distances required, or by forming the orifices 300 of varying diameters and spacing them uniformly lengthwise of the cylinder, all as required in accordance with known procedures in this 311'. to achieve substantially constant force travel closure characteristics. As many orifices 300 may be provided in the cylinder 234 as may be required for elficient operation of cushioning device 82. A typical arrangement of the orifices to achieve the substantial constant travel characteristic is described in my US. Patent 3,216,592. It is to be noted that the orifices 300 are arranged so that the substantially constant force travel characteristic is also obtained during the return stroke of the piston head after the buff impact has been dissipated.

The housing 232, cylinder 234, piston member 220, and the remaining components of cushioning device 82 are proportioned to provide a long travel cushioning stroke which may be in the range of from about 20 inches to about 40 inches, prefer-ably 30 inches.

The end plate 276 of cushion device 82 is formed to define a threaded opening 302 which threadedly receives an annular collar 304 through which the piston rod 224 extends. Interposed between the piston rod and the collar is a non-metallic ring 306 that is preferably formed of a laminated resin, such as the type designated by the National Electrical Manufacturers Association as 9 coarse, grade C. Preferably the plastic ring 306 has an ID. that substantially complements the CD. of the piston rod, and which is sufficiently less than the ID. of the collar 304 at its annular opening 308 to avoid metal to metal contact between ring 306 and the piston rod 24. Ring 306 is seated in annular recess 310 of collar 104.

The collar 304 is also formed with a plurality of ports or passages 312 and an annular flange portion 314 that receives an annular flap valve plate 316 which is secured against displacement from flange portion 314 by a suitable locking ring 318.

As indicated in FIGS. 6 and 8, end plate 276 has secured thereto by appropriate bolts (indicated in dashed lines at 320 in FIG. 6) a base plate 322 that defines a radially inwardly extending annular ridge portion 324 through which piston rod 224 extends.

The base plate 322 on its end plate side defines a recess 325 that is quadrilateral in configuration and substantially complements the exterior transverse cross-sectional configuration of plate 322; recess 325 receives the collar 304 when the base plate 322 is secured to the end plate 276, as indicated in FIGS. 6 and 8. As the collar 304 is round or cylindrical in configuration, the base plate 322 recess 325 defines with the collar 304 at each of the four corners of the base plate 322 a passage 328 which in accordance with the present arrangement is aligned with a correspondingly placed passage 326 formed in the end plate 276 in the manner suggested in FIG. 8. This provides for hydraulic liquid communication between the reservoir 296 and external surface 329 of the piston rod 224 eX-teriorly of the collar 304 through the four corners of the abutting plates 276 and 322. Hydraulic liquid communication is also provided between the same portion of the piston rod 224 and the chamber 294 through ports 312 of collar 304 and around flap plate 316, when the flap plate 316 is not seated in check valve closing relation over the ends of the ports 312 (plate 316 is proportioned to do this, as indicated in FIG. 6).

End plate 277 at each of its four corners is provided with a passage 330 which provides hydraulic liquid communication between reservoir 2% and recesses 332 which are formed at each corner (see FIG. 8 and my said copending application Ser. No. 439,630). Each recess 332 is sealed shut by Welding in place an appropriate cover element 334, and each recess 332, and with the cover plate 334 defines a passage 336, communicates with chamber 294 through passages 338 formed in the end .plate 277.

As indicated in FIG. 8, the passages 33S terminate in an annular recess 340 formed in the inner face of end plate 377 in which an annular member of ring 342 is fixed, as by welding at 343. Annular member or ring 342 has mounted therein an annular flap valve plate 344 which is secured against displacement within the ring 342 by a suitable locking ring 346.

Thus, hydraulic liquid communication is provided between reservoir 296 and chamber 294 through passages 330, 336, 338, when flap valve plate 340 is displaced from check valve closing relation with respect to passages 338. Flap valve plate 342 is proportioned to overlie the passages 338, as indicated in FIG. 6.

It will thus be seen that the end plates 276, 277 and base plate 322 are quadrilateral in transverse crosssectional configuration and are provided with hydraulic liquid conducting passageways at their four corners.

Secured to the annular ridge portion 324 of base plate 322 is one end 350 of an annular flexible static seal member or boot 352 that has its other end 354 turned outside in, with said end 354 being secured to the piston rod 224.

In the case of the boot end 350, this place is locked between a shoulder 356 and a ring 358 held in place by a suitable looking ring 360, while in the case of the boot end 354, it is held in place by being secured between a pair of annular members 362 and 364 against which abut the respective sleeves 366 and 368 that are held in place by suitable locking rings 370 and 372, respectively. Parenthetically, all locking rings referred to herein, such as rings 370 and 372, are seated in appropriate recesses, in accordance with standard practice in connection with such devices.

The annular static seal member or boot 352 thus defines with the piston rod 224 an annular hydraulic liquid receiving chamber 374.

Base plate 322 has aflixed thereto as by welding an annular extension ring or cylinder 376, which is proportioned to overlie the boot 352 when the hydraulic cushion device 82 is in its contracted relation.

Base plate 322 is formed with an endless recess 378 about its recess 325 which receives a suitable O-rin'g seal 380 for insuring a hydraulic liquid seal between the base plate 322 and end plate 376 (see FIG. 6). This has been omitted from the showing of FIG. 8 to simplify the drawing of that figure.

The piston member 220 in accordance with this invention is a one piece element formed from a suitable forging steel or the like to permit the piston head 222 to be formed to a suitable piston head configuration by an appropriate forging operation. One suitable material for this purpose is C-1050 steel, normalized and of a suitable forging quality.

The rim 390 of the piston head is suitably machined to form annular recess 392 in which a laminated plastic ring 394 is mounted. Ring 394 is preferably made of the same substance as ring 306, and preferably has an CD. that exceeds that of piston head rim 390 suificiently to prevent metal to metal contact between piston head 222 and cylinder 234.

The piston rod 224 at its outwardly extending end 391 is fixed (as by Welding or screw threading) to a plate structure 393 that has a transverse cross-sectional configuration similar to that of end plates'276 and 277 and base plate 322. Recentering spring 395 is seated between base plate 322 and plate structure 393 and returns the hydraulic cushion 82 and sill arrangement 14 to their extended relations after a buff impact has been cushioned. Plate structure 393 comprises a spring plate 397 that is integrally connected to lug or key 48.

Cushion device end plates 27 6 and 277, base plate 322, and spring plate 397 are proportioned to fit easily within but substantially complement the interior configuration of fixed sill 26, with the result that the sill. 26 guides the contracting and extension action of cushion device 82.

The pressure relief valve 83 in accordance with this invention is mounted entirely within the piston member 220. As indicated in FIGS. 68, the piston member 220 is formed with a longitudinally extending 'bore 400 that is counterbored as at 402 to receive compression spring 404 which extends into a cylindrical valve chamber 406 in which is slidably mounted an annular ring valve or valve stem member 408 that preferably has an CD. that substantially complements the TD. of the chamber 206. Fixed to the tubular valve stem member 408 are a plurality of studs or pins 410 that extend longitudinally of the axis of bore 400 and chamber 406 and bear against a disc 412 that has secured thereto a pin 414 which also extends longitudinally of the axes of bore 400 and chamber 406. The pin 414 is slidably mounted within a bore 416 formed in a retainer nut 418 that is threadedly mounted at the piston head end of chamber 406.

The piston member 220 is formed with a plurality of diagonal passages 420 defining inlet ports 422 at the working face or high pressure side 424 of the piston head 2'22 and exhaust ports 42-6 opening into chamber 406. Piston member also is preferably formed with radial passages 421 defining inlet ports 423 at the side 425 of piston rod 224 and exhaust ports 427 opening into chamber 406, with passages 420 and 421 being in alternating relation about the axis of rod 224.

The bore 400 communicates with a plurality of cross bores 428 that extend transversely of the piston rod 224 and terminate in exhaust ports 430 which are directed laterally of the piston rod. As indicated in FIG. 6, the sleeve 366, in accordance with this invention, is preferably formed with an extension 432- which overlies the ports 430 and deflects hydraulic liquid discharge from ports 430 to the left as viewed in FIG. 6 rather than directly against the static seal member 352.

Spring 404 is selected to have a strength such as to hold the tubular valve stem member 408 substantially in the position shown in FIG. 6 during normal operation of the gear on cushioning buff. However, the strength is selected such that when excessive buff impact conditions cause pressures to rise in chamber 294 to about 85 to 90 percent of the strength of cylinder 234, the pressure acting on the end 434 of pin 214 will force stem 408, through disc 412 and pins 410, to the right of FIG. 6 to the extent that ports 426 and 423 will be opened to chamber 406 and thus to bore 400 through the hollow center of the helical spring 404. This permits hydraulic liquid to discharge through the relief valve 83 and to chamber 374, and also to discharge through passages 421 to the back side of the piston and thus relieve the excess pressures building up in cylinder 34.

The arrangement of valve 83 as illustrated and described permits the use of a spring with a relatively light preload to adequately protect the hydraulic cushion unit. For instance, spring 404 can be arranged to have a preload as light as on the order of two hundred and eighty pounds, and yet hold the valve 83 closed up pressures on the order of twelve thousand p.s.i. in chamber 294. A suitable spring for this purpose is formed from vanadium steel or its equivalent into four gauge wire size and provided with a spring rate of 131.6 pounds per inch with twenty-six active coils and an outside diameter of one and onequarter inches.

In use, the hydraulic cushioning unit 82 is fully charged with hydraulic liquid in the spaces defined by the reservoir 296, the chamber 294, the chamber 374, and all passages connecting same. This may be done in any suitable manner, but care should be taken to have all air bled out of the system while at the same time avoiding overcharging of the unit. The boot 352 should be disposed substantially as shown in the full lines of FIG. 6 when properly charged with hydraulic liquid.

In normal buff impact absorbing operation, the piston member 220 moves from the full line position to the broken line position of FIG. 6, and the valve 83 remains closed. As the piston head moves between these two positions, hydraulic liquid discharges from chamber 294 through the orifices 300 into reservoir 296 and returns to the chamber 294 on the other side of the piston head 222 through the orifices 300 that the piston head 222 has passed, as well as through passages 326, 328, 312 and valve plate 316. Flap valve plate 344 under the pressure build up before piston side 424 shuts oil the passages 338 in the end plate 377. This hydraulic liquid flow through the orifices 300 creates a substantially constant force travel characteristic and continues until the piston head reaches its maximum extent of buff absorbing travel (approximately the broken line position of FIG. 6) after which the compression spring 395 acting on base plate 322 and spring plate 397, and therefore on piston rod 224, draws the piston member 220 to the right of FIG. 6 and reverses the hydraulic liquid fiow into chamber 294. The hydraulic liquid flow will then be from the side 425 of piston head 222 through the orifices 300 on the high pressure piston side 425 and to reservoir 296 and then back into chamber 294 through those of the orifices 300 that have been opened by the movement to the right of FIG. 6 of the piston member 220. During the return flow through the orifices 300 the flow is again such as to impart a substantially constant flow characteristic to the cushion device 42. Also, flap valve plate 316 will close off passages 312 and hydraulic liquid flow will occur between reservoir 296 and chamber 294 through passages 330, 336 and 338 of end plate 377 and past flap valve plate 344.

One function of the flexible static seal 352 is to form an accumulator chamber to take the hydraulic liquid displaced from chamber 294 by the entry of the piston rod 224 into same, and the seal member 352 expands somewhat under the pressure of the additional hydraulic liquid discharged into the chamber 374. The member 352 is made sufficiently resilient so that as the piston member 220 returns to the full line position of FIG. 6, it tends to aid in discharging hydraulic liquid from chamber 374 back through the passages 328 and 32.6 and into reservoir 296, etc. Chamber 374 also serves as a surge chamber to take care of excessive pressure surges in reservoir 296; pressures in reservoir 296 are relieved through passages 326 and 328.

It will therefore be seen that I have provided a long travel dual sill arrangement with a double acting hydraulic cushioning device incorporated therein that forms a unique sliding sill or draft and bufiing column cushioning arrangement for protecting both the car and its lading against coupler impacts.

My new sliding sill or draft and bufling column arrangement is especially suited for ready converting of existing standard boxcars to cushion underframe cars, This arrangement is largely self-contained from a cushioning standpoint, and insofar as modification of existing underframes is concerned, the only important changes required are those involved in applying the fixed stops to the underframe stationary center sill structure, as well as the necessary supports for supporting and guiding the sliding sill itself.

When a longitudinal impact is encountered, as, for example, against the right hand end of the sliding sill arrangement 14 of FIG. 1, the sill section moves to the left of FIG. 1 with respect to underframe 12 with the result that the casting of column section end 38 presses against end 44 of cushion device 42. This action presses the end 46 of the cushion device 42 against the casting 110 of the end 40 of column section 36, which in turn presses the rubber pad cushioning device 62 against the stop structures 70 and 78 that are afiixed with respect to the center sill structure 26. As the cushion device 62 acting on stop structures 7-0 and 78 prevents any substantial movement of the cushion device 42 to the left of FIG. 1 under the impetus of the buff impact, the cushion device 42 contracts under the action of column section 34 continuing to move to the left of FIG. 1 against the action of cushion device recentering spring 395, with the result that the piston member 220 moves from the full line position of FIG. 6 to the broken line position of FIG. 6 to provide the long travel cushioning action having a substantially constant force travel characteristic.

After the. cushion device has completed its closure stroke, the recentering spring 395 or a draft force applied at the right hand returns the hydraulic cushion device piston member 220 to its full line position of FIG. 6, and at the same time moves column section 34 to the right of FIG. 1 to return the column arrangement 14 to its extended full line position shown in FIG. 1, which is reached when cushion device 60 follower plate 63 seats against stops 68 and 76. During the return movement the cushion device 42 as heretofore described is characterized by a substantially constant resisting force during its travel.

Coupler impacts in bufi from the other direction are handled in a similar manner, though in the opposite directions, and in this case, the fixed stop structures 68 and 76 form the means for transmitting the impact energy to the underframe and the weight that it carries. Coupler impacts from the left of FIG. 1 cause the housing 232 of cushioning device 82 to move with respect to its piston member 222, but the hydraulic liquid flows above described remain the same.

It will thus be seen, assuming a car in question includes underframe 12 and is subjected to a free standing impact, the impacted end of the draft and buffing column moves with respect to the underframe against the cushioning device, while the other end of the draft and bufing column remains substantially stationary relative to the underframe throughout the stroke of the cushioning device.

When the car including underframe 12 and cushioning arrangement 14 is at the end of a cut of cars and is impacted, the column section impacted moves inwardly of the car with respect to underframe 12, and since the struck column section in the ordinary functioning of cushioning arrangement 14 travels the full stroke length of the cushioning device 42 with respect to the other column section, the impacted car will be protected as the hydraulic cushion device 82 performs its energy transmittin-g and dissipating functions with substantially constant force travel closure characteristics over the indicated travel length.

The cushioning device 42 does not come into play when draft impacts are applied on the car and the piston member 220 is in the full line position shown. For instance, assuming that the coupler 104 of column section 34 is subjected to a draft impact, the column section 34 tends to move to the right of FIG. 1 with respect to underframe 12 (carrying with it column section 36), thereby compressing rubber pad cushioning device 60 between the face 66 of casting 110 of the column section end 38 and faces 176 and 186 of stop structures 68 and 76, respectively. The cushioning device 60 is arranged to provide a travel on the order of that of conventional draft gear to handle the draft impact, for instance, in the range of two to five inches, after which the resilience of the cushioning device 60 returns the draft impacted column section 34 (as well as column section 36) to the left of FIG. 1 with respect to underframe 12 to recentered position.

Draft impacts at the other end of the underframe are handled in like manner, but in reverse directions, the cushion device 62 having a travel similar to that of device 60.

The cushioning device 82 includes a number of improvements in addition to the pressure relief valve 83.

As already mentioned in connection with the hydraulic cushioning device, the piston member 220 is a one piece element, which eliminates the need to weld the piston head on a piston rod and the consequent distortion due to heat treating and welding.

Furthermore, it will be noted that the boot 352 not only serves to accumulate the hydraulic liquid displaced from the chamber 294 by the full entry of the piston rod into that chamber, but it also serves as a surge chamber to minimize forces within the reservoir 296 in the 12 chamber 294 during displacement of the hydraulic liquid by the piston 220.

The hydraulic cushion device piston arrangement also eliminates to a considerable extent the machining that has formerly been required in connection with components of this type.

Pressure relief valve 83 is simple and reliable, and does not require a sensitive adjustment to adapt it to its desired working condition. The valve 83 is entirely housed Within the piston member 220, and thus is not only compactly arranged, but fully protected during use.

Another important aspect of this invention is that the low car body forces provided by practicing the inven tion of my Patent 3,003,436 are also available to the sliding sill itself, which means that substantially lighter sliding sill constructions may be employed than was heretofore thought possible.

Still another important aspect of the invention is that since the end of the car sill that is impacted moves inwardly of the car without the sill at the other end of the car moving outwardly of the car, the uncoupling device at each end of the car can be greatly simplified.

Moreover, Where a cushion car equipped with this invention is at the end of a cut of cars and is impacted, the car next to it received the benefit of long travel cushioning, whereas with a cushion underframe car with a continuous sliding sill, this was not possible.

The foregoing description and the drawings are given merely to explain and illustrate my invention and the invention is not to be limited thereto, except insofar as the appended claims are so limited, since those skilled in the art who have my disclosure before them will be able to make modifications and variations therein without departing from the scope of the invention.

What is claimed is:

1. In a railway vehicle including a wheel frame structure, a draft and buffing column carried by said frame structure and including means for securing a coupler at each end thereof, cushioning means operatively interposed between stop means fixed on said frame structure and said column for cushioning longitudinal impacts applied to the couplers, the improvement wherein:

said column comprises a pair of sections positioned in spaced apart relation in longitudinal alignment and mounted for movement longitudinally thereof with respect to each other and to said frame structure,

said columns each include keying means at the adjacent ends thereof, and formed to define a cushion pocket outboard of said keying means,

a resilient cushioning device mounted in each of said cushion pockets in engagement with said stop means so as to be operative to absorb draft impacts applied on said column when said column sections are in said spaced position,

a hydraulic cushioning means comprising a self-contained hydraulic unit disposed between said sections, a hydraulic fluid filled cylinder, a piston assembly reciprocable therein, and means arranged to displace fluid in a manner to achieve a substantially constant force travel characteristic when said cylinder and said piston assembly are reciprocated relative to each other upon bufi' impact applied on said column, and having a length of travel substantially equal to said spaced distance between said sections,

means for detachably keying said cylinder for movement with one of said columns,

means for detachably keying said piston member for movement with the other of said columns,

and return spring means disposed between said cylinder and said piston assembly for returning said column sections to a spaced position after a buff impact has been dissipated.

2. The improvement set forth in claim 1 wherein:

said keying means on each of said columns comprises vertically disposed open socket means and said keying means of said hydraulic cushion means comprises vertically disposed lug means interenga'ging said open socket means,

and support means removably secured to said frame structure and underlying said unit,

whereby, on removal of said support means, said unit may be lowered to separate said keying means and remove said unit from between said sections.

3. The improvement set forth in claim 2 wherein:

said resilient cushioning devices being resiliently compressible longitudinally of said column and each defining an end portion facing the coupler ends of said column,

and said stop means comprises lug means engaging the respective resilient cushioning device end portion and fixed to said frame structure.

4. The improvement set forth in claim 3 wherein:

said column sections each comprise elongate members having an H configuration in transverse section and defining a horizontally disposed Web portion,

and wherein said web portions of said sections are interrupted adjacent said socket structures to receive the respective resilient cushioning devices. 5. The improvement set forth in claim 4 wherein: said resilient cushioning devices are T-shaped in transverse cross-sectional configuration with the upper portions thereof being proportioned to rest on the respective web portions.

References Cited ARTHUR L. LA POINT, Primary Examiner. DRAYTON E. HOFFMAN, Eydamt'ner. 

1. IN A RAILWAY VEHICLE INCLUDING A WHEEL FRAME STRUCTURE, A DRAFT AND BUFFING COLUMN CARRIED BY SAID FRAME STRUCTURE AND INCLUDING MEANS FOR SECURING A COUPLER AT EACH END THEREOF, CUSHIONING MEANS OPERATIVELY INTERPOSED BETWEEN STOP MEANS FIXED ON SAID FRAME STRUCTURE AND SAID COLUMN FOR CUSHIONING LONGITUDINAL IMPACTS APPLIED TO THE COUPLERS, THE IMPROVEMENT WHEREIN: SAID COLUMN COMPRISES A PAIR OF SECTIONS POSITIONED IN SPACED APART RELATION IN LONGITUDINALLY ALIGNMENT AND MOUNTED FOR MOVEMENT LONGITUDINALLY THEREOF WITH RESPECT TO EACH OTHER AND TO SAID FRAME STRUCTURE, SAID COLUMNS EACH INCLUDE KEYING MEANS AT THE ADJACENT ENDS THEREOF, AND FORMED TO DEFINE A CUSHION POCKET OUTBOARD OF SAID KEYING MEANS, A RESILIENT CUSHIONING DEVICE MOUNTED IN EACH OF SAID CUSHION POCKETS IN ENGAGEMENT WITH SAID STOP MEANS SO AS TO BE OPERATIVE TO ABSORB DRAFT IMPACTS APPLIED ON SAID COLUMN WHEN SAID COLUMN SECTIONS ARE IN SAID SPACED POSITION, A HYDRAULIC CUSHIONING MEANS COMPRISING A SELF-CONTAINED HYDRAULIC UNIT DISPOSED BETWEEN SAID SECTIONS, A HYDRAULIC FLUID FILLED CYLINDER, A PISTON ASSEMBLY RECIPROCABLE THEREIN, AND MEANS ARRANGED TO DISPLACE FLUID IN A MANNER TO ACHIEVE A SUBSTANTIALLY CONSTANT FORCE TRAVEL CHARACTERISTIC WHEN SAID CYLINDER AND SAID PISTON ASSEMBLY ARE RECIPROCATED RELATIVE TO EACH OTHER UPON BUFF IMPACT APPLIED ON SAID COLUMN, AND HAVING A LENGTH OF TRAVEL SUBSTANTIALLY EQUAL TO SAID SPACED DISTANCE BETWEEN SAID SECTIONS, MEANS FOR DETACHABLY KEYING SAID CYLINDER FOR MOVEMENT WITH ONE OF SAID COLUMNS, MEANS FOR DETACHABLY KEYING SAID PISTON MEMBER FOR MOVEMENT WITH THE OTHER OF SAID COLUMNS, AND RETURN SPRING MEANS DISPOSED BETWEEN SAID CYLINDER AND SAID PISTON ASSEMBLY FOR RETURNING SAID COLUMN SECTIONS TO A SPACED POSITION AFTER A BUFF IMPACT HAS BEEN DISSIPATED. 